Please help! After a very hot summer of little to no hot tub use, I opened the cover to find a brown sticky ring around the tub. I drained the tub, cleaned it, and refilled it. I checked my chemicals and shocked. I added ph balance and also calcium increaser, as well as metal and stain control. After a couple of hours my new, clean water is cloudy, almost a milky blue. I also put in a new filter and mineral sanitizer when I refilled. What is going on?